1. Field of the Invention
The present invention is directed to a torsional vibration damper arrangement having a driving transmission device and a driven transmission device rotatable around an axis of rotation counter to the action of a damping arrangement with respect to the driving transmission device. The damping arrangement includes at least one damper unit with a plurality of spring units arranged successively in circumferential direction. The driving transmission device and the driven transmission device have circumferential supporting areas for the at least one damper unit, the latter being supported thereon by circumferential ends, and a radial supporting arrangement for radial support of the damper unit in an intermediate supporting area between the circumferential ends thereof. The radial supporting arrangement includes at least one annular radial supporting member with radial supporting units, at least some of which are intended to receive spring cups to enter into an operative connection with the respective associated intermediate supporting areas of the damper unit by these spring cups, a circumferential projection which is provided at the respective spring cup and which penetrates into the associated spring unit is enclosed by the respective intermediate supporting area of this spring unit. The at least one annular radial supporting member is rotatable around the axis of rotation with respect to the driving transmission device and the driven transmission device.
2. Description of the Related Art
A torsional vibration damper arrangement of the type mentioned above is known, from DE 10 2006 052 853 A1 in which two damper units are radially offset with respect to one another. The spring units of the radially inner damper unit are received in spring windows and are relatively short in circumferential direction so that there is little evidence of any negative influence of centrifugal force. In contrast, a large spring volume is introduced by the spring units of the radially outer damper unit so that there is a risk that these springs will be displaced radially outward under the influence of the centrifugal force at least along some of their extension length on the circumference side. In order to mitigate such a process, the individual spring units are supported not only in circumferential supporting areas of the driving transmission device and driven transmission device but also in circumferential direction therebetween, namely, by radial supporting units that engage at intermediate supporting areas of the spring units. For this reason, DE 10 2006 052 853 A1 shows a construction for a torsional vibration damper arrangement in which annular radial supporting members extend radially inside the spring units and reach into the intermediate supporting areas of the spring units toward the radial outer side with radial supporting units. A construction of this kind is shown, for example, in FIG. 21 or FIG. 22. In this construction, recesses are provided at the respective radial supporting unit and projections of the spring cups engage in these recesses. Further, these spring cups have circumferential projections which penetrate into the associated spring unit to a depth of a maximum of one turn.
While the spring units of the radially outer damper unit in the known torsional vibration damper arrangement may be supported against the effect of centrifugal force with minimal friction, the support is moderate when the spring units are long in the circumferential direction, so that there is inevitably an appreciable bending of the spring unit radially outward in spite of the radial supporting arrangement in the intermediate supporting area. This fundamental problem may lead to the problem of an undesirably severe deflection particularly in spring units with low torque transmission capacity. However, it is precisely spring units of this kind which allow excellent decoupling for torsional vibrations under small loads, i.e., when low torque is applied, and which further necessitate a special arrangement for limiting rotational angles to prevent the turns of this spring unit from making contact when higher torques are applied. While the arrangement for limiting rotational angles in the known torsional vibration damper arrangement may protect the radially outer damper unit in its entirety, it does not protect an individual spring unit of this damper unit that is designed for low torque.